With the development of mobile communication technology, new mobile communication access networks have been continuously established and put into use by mobile communication operators, such as 3G access network and LTE access network. At the same time, the existing mobile communication access networks are also reserved by the operators, such as GSM access network. As a result, multiple mobile communication access networks are coexisting.
However, different mobile communication access networks have different advantages. For example, network coverage of GSM access network is broader so as to provide better voice call service to users; the network speed of TD-SCDMA access network or WCDMA access network is faster so as to provide high-speed data service to users; while LTE access network can provide even higher-speed service with low delay so as to provide high-definition sound in real time and high-speed data service to users.
In order to make full use of the advantages of different access networks, there is a trend to integrate a plurality of network access techniques in a same operator network. Therefore, user can use one mobile communication terminal to access different access networks. Moreover, different services can be provided through different access networks.
During the integration of multiple access technologies, a single-(U)SIM dual standby/multiple standby mobile communication terminal is used. It uses one (U)SIM but can access to multiple access networks at the same time, and can supply services of different types by means of the multiple access networks.
In the prior art, when the single-card dual standby/multiple standby mobile communication terminal is in a standby state or is providing the user with services, if the coverage in one of the access networks is lost, a corresponding communication system losing coverage in an access network needs to perform full-band search in the access network, so as to find a cell suitable for camp-on and recover the services.
Because the above-mentioned searching method requires the mobile communication terminal to perform full-band search in the access network in which the coverage is lost, the power consumption of the mobile communication terminal will be increased remarkably.